Calciphylaxis in a hemodialysis patient: appearance after parathyroidectomy during a psoriatic flare.

Chronic renal failure patients are prone to soft tissue calcifications. A phenomenon of acute ischemic skin necrosis and dermohypodermic arteriolar medial calcification has been described recently in patients with chronic renal failure and secondary hyperparathyroidism (HPT). This phenomenon, termed calciphylaxis, occurs in response to certain factors, the most important of which appears to be an elevated blood calcium-phosphate product. Accordingly, parathyroidectomy in addition to normalization of calcium-phosphate product has been proposed as the only effective therapeutic approach for this condition. We describe a case of chronic renal failure with severe secondary HPT in which the patient developed calciphylaxis 4 days after the appearance of a psoriatic flare. Four months before, a subtotal parathyroidectomy was performed for severe HPT and at the time the ulcerations appeared, blood calcium-phosphate product was correct. Etiological and physiopathological aspects of calciphylaxis are discussed.